Unscrew tight screw on the power supply

As the title says, I was trying to disassemble my PS3 with the guide from the page and I came across a screw that won’t turn just on the power supply. I’ve tried the rubber trick but with no luck and being a place so near the motherboard and the power supply itself, I’d rather not put any liquids near it. Any suggestions on what I could do or get to unscrew it? I attach below a picture of the screw that I’m talking about for better reference.